High-pressure Roll Presses
These consist of a pair of rollers set 8ā30 mm apart and counter-rotating with surface speed around 0.9 - 1.8 m.sā1. The bearings of the rollers are designed to deliver a pressure of 50 MPa or more. The bed of material drawn between the rollers emerges as a slab-like agglomeration of highly fractured particles. The energy efficiency of this process is comparatively high. Systems have been designed, including a de-agglomerator and separator, that will deliver material of cement fineness. However, particle size distribution is again a problem, and roll presses are now increasingly popular as a "pre-grind" process, with the cement finished in a single chamber ball mill. This gives good cement performance, and reduces energy consumption by 20-40% compared with a standard ball mill system.
Read more about this topic: Cement Mill
Famous quotes containing the words roll and/or presses:
“Rock ‘n’ roll is a combination of good ideas dried up by fads, terrible junk, hideous failings in taste and judgment, gullibility and manipulation, moments of unbelievable clarity and invention, pleasure, fun, vulgarity, excess, novelty and utter enervation.”
—Greil Marcus (b. 1945)
“Gratitude is a fickle thing, indeed. A person taking aim presses the weapon to his chest and cheek, but when he hits, he discards it with indifference.”
—Franz Grillparzer (1791–1872)